Modem telecommunications switching systems are controlled by data processing systems. These data processing systems are controlled by a program stored in the memory of the data processing system. As demands for more features and improved capacity evolve over time, the program for these systems is changed to adapt them to these new requirements. Usually, program changes are introduced with a "new release", although, of course, small errors are frequently corrected through small changes in the program.
The changes in the program are frequently accompanied by changes in the memory; both the random access memory (RAM), and the bulk memory such as this used by these systems since the changes frequently require more memory, and since new types of faster and higher capacity bulk memories are constantly being introduced in the market.
A problem arises in switching systems and other real time systems whose operation cannot be interrupted in introducing such changes without disrupting service. Methods have been found for introducing new releases one step at a time through the use of special conversion software to convert the data base from one release to the next, the conversion software being written specifically for this single step conversion, and for making the transition from one release to the next through a process which involves the use of the duplicate equipment that is provided in the control processors. One processor controls the system under the old release while the second processor is being loaded with the program and data base of the new release. A transition is made to control by the second processor and its memory, and the first processor is kept in the old release until it has been determined that the system operates satisfactorily under the control of the second processor. Thereafter, the first processor is updated with the new release and the data base for the new release, and the system operates under the new release.
This solution is unsatisfactory for the case in which it is desired that a switching system be updated by several release steps. The method requires that such updating be performed one step at a time, preferably with a substantial time within each step to insure that the system is still operating satisfactorily. The demand for multiple step upgrade is quite high since many telephone administrations chose to stay in one release for a number of years until there is an overwhelming need for a new release; at that time, the normal procedure is to upgrade immediately to the newest release.
A problem of the prior art is that there is no satisfactory way of performing a single jump multiple release upgrade in a switching system or other real time control systems.
Solution
The above problem is solved and an advance is made over the prior art in accordance with our invention wherein a multiple step release is made by having a transition from the early release to a state wherein one of the duplicate control processors operates using a new bulk memory pre-initialized with the data base and program of the new release; after a period of satisfactory operation in the new release, the second processor is also connected to a newly initialized bulk memory, and the system operates in the new release. Advantageously, the jump is accomplished as a single upgrade process. Advantageously, this arrangement does not require any special jump retro-fit software support. Advantageously, such an arrangement avoids the cost of hardware required for intermediate releases, but not required for the initial and final release. Advantageously, the upgrade can be accomplished in a single jump process instead of a group of smaller upgrades.
In accordance with applicants' preferred embodiment, the transition of each of the two processor and associated bulk memory is accomplished by taking the processor out of service and reconnecting the cable to bulk memory from the initial bulk memory to the new bulk memory. Advantageously, such an arrangement avoids the requirement for multiple memory ports to support the transition.
In applicants' preferred embodiment, the data base is updated one release at a time using the software for making the transition in the data base from one release to the next. This updating is performed off-line and the new release version of the data base, as well as the new release version of the program is then initialized into the new bulk memory. In applicants' preferred embodiment, this off-line process is performed in a worling switch using a simplex moving head drive. Advantageously, such an arrangement avoids the necessity for additional software development for the conversion of the data base for a jump in releases, or alternatively, avoids the long and labor-intensive process of implementing a multiple release change through a series of single release changes.